Lumsing Harmonica Style Power Bank External Battery for iPhone iPad

When you are away from the office for an extended time, it is often useful to have a portable battery with you.  And nowadays, when many of us have both an iPhone and an iPad, it is even more useful to have a battery that is designed to work with either one.  Because the iPad has such a large battery, when you carry an external backup battery that works with the iPad, you always need to balance capacity versus the size and weight and cost of that battery.  The Lumsing 10400 mAh Harmonica Style Portable Power Bank strikes the right balance — large and heavy enough to get the job done, but small and sleek enough that you won't mind carrying it with you.  Lumsing sent me a free unit to review, and I have been testing it for the last week.  I like it a lot.  This looks like a great battery to toss in your briefcase or purse.

Design and Features:
My main concern with an external battery is simply that it work well, but since you are going to carry this thing around a lot, it is nice to have something that has a pleasing design.  I was very impressed with this device.  As the "Harmonica" in the name implies, this device is shaped like a long rectangular box which is curved on one long end and is tapered on the other.

The Lumsing Power Bank is about 5.5 inches long, almost 2.5 inches deep, and is about .8 inches high.

The curve on one of the long sides of this device makes it feel good when you hold it in your hand.  A minor feature perhaps, but one that I liked.

The device weighs 8.35 oz.  (An iPhone 5S weighs 4 oz; an iPhone 4S weighs 4.9 oz.)  You probably won't notice 8.35 oz. in a purse or briefcase, but you'll definitely notice it if you slip it into the pocket of your pants.

The power banks tapered end contains most of the inputs and controls.  First, there are two ports, one which provides 1 Amp and one that provides 2.1 Amps.  You can use either port with an iPhone, and as noted below, you will get a slightly faster charge with the 2.1 Amp output.  For an iPad Air, you'll want to use the 2.1 Amp port.